182 research outputs found

    A study to develop and implement differentiated, hands on mathematics instruction strategies to improve student learning

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    The purposes of the study were to research, develop and implement differentiated, hands on mathematics instruction strategies with mathematics teachers in grades six through eight for improvement of student learning. Teachers, through collaborative action research, created and implemented student centered, discovery based, hands on, manipulative centered lessons over two marking periods which provided students with experiential, problem solving, mathematical situations that met their individual and group needs. Analysis of this case study yielded growth through a triangulation of data measured from improved student scores, student observations, and teacher reflection about their pedagogy. Effective classroom strategies for differentiated, hands on instruction are discussed

    Nutrients and pathways that regulate health span and life span

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    Both life span and health span are influenced by genetic, environmental and lifestyle factors. With the genetic influence on human life span estimated to be about 20\u201325%, epigenetic changes play an important role in modulating individual health status and aging. Thus, a main part of life expectance and healthy aging is determined by dietary habits and nutritional factors. Excessive or restricted food consumption have direct effects on health status. Moreover, some dietary interventions including a reduced intake of dietary calories without malnutrition, or a restriction of specific dietary component may promote health benefits and decrease the incidence of aging-related comorbidities, thus representing intriguing potential approaches to improve healthy aging. However, the relationship between nutrition, health and aging is still not fully understood as well as the mechanisms by which nutrients and nutritional status may affect health span and longevity in model organisms. The broad effect of different nutritional conditions on health span and longevity occurs through multiple mechanisms that involve evolutionary conserved nutrient-sensing pathways in tissues and organs. These pathways interacting each other include the evolutionary conserved key regulators mammalian target of rapamycin, AMP-activated protein kinase, insulin/insulin-like growth factor 1 pathway and sirtuins. In this review we provide a summary of the main molecular mechanisms by which different nutritional conditions, i.e., specific nutrient abundance or restriction, may affect health span and life span

    Nutraceutical Activity in Osteoarthritis Biology: A Focus on the Nutrigenomic Role

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    Osteoarthritis (OA) is a disease associated to age or conditions that precipitate aging of articular cartilage, a post-mitotic tissue that remains functional until the failure of major homeostatic mechanisms. OA severely impacts the national health system costs and patients' quality of life because of pain and disability. It is a whole-joint disease sustained by inflammatory and oxidative signaling pathways and marked epigenetic changes responsible for catabolism of the cartilage extracellular matrix. OA usually progresses until its severity requires joint arthroplasty. To delay this progression and to improve symptoms, a wide range of naturally derived compounds have been proposed and are summarized in this review. Preclinical in vitro and in vivo studies have provided proof of principle that many of these nutraceuticals are able to exert pleiotropic and synergistic effects and effectively counteract OA pathogenesis by exerting both anti-inflammatory and antioxidant activities and by tuning major OA-related signaling pathways. The latter are the basis for the nutrigenomic role played by some of these compounds, given the marked changes in the transcriptome, miRNome, and methylome. Ongoing and future clinical trials will hopefully confirm the disease-modifying ability of these bioactive molecules in OA patients

    Modulation of Fatty Acid-Related Genes in the Response of H9c2 Cardiac Cells to Palmitate and n-3 Polyunsaturated Fatty Acids

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    While high levels of saturated fatty acids are associated with impairment of cardiovascular functions, n-3 polyunsaturated fatty acids (PUFAs) have been shown to exert protective effects. However the molecular mechanisms underlying this evidence are not completely understood. In the present study we have used rat H9c2 ventricular cardiomyoblasts as a cellular model of lipotoxicity to highlight the effects of palmitate, a saturated fatty acid, on genetic and epigenetic modulation of fatty acid metabolism and fate, and the ability of PUFAs, eicosapentaenoic acid, and docosahexaenoic acid, to contrast the actions that may contribute to cardiac dysfunction and remodeling. Treatment with a high dose of palmitate provoked mitochondrial depolarization, apoptosis, and hypertrophy of cardiomyoblasts. Palmitate also enhanced the mRNA levels of sterol regulatory element-binding proteins (SREBPs), a family of master transcription factors for lipogenesis, and it favored the expression of genes encoding key enzymes that metabolically activate palmitate and commit it to biosynthetic pathways. Moreover, miR-33a, a highly conserved microRNA embedded in an intronic sequence of the SREBP2 gene, was co-expressed with the SREBP2 messenger, while its target carnitine palmitoyltransferase-1b was down-regulated. Manipulation of the levels of miR-33a and SREBPs allowed us to understand their involvement in cell death and hypertrophy. The simultaneous addition of PUFAs prevented the effects of palmitate and protected H9c2 cells. These results may have implications for the control of cardiac metabolism and dysfunction, particularly in relation to dietary habits and the quality of fatty acid intake

    NOTCH1: A Novel Player in the Molecular Crosstalk Underlying Articular Chondrocyte Protection by Oleuropein and Hydroxytyrosol

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    Osteoarthritis (OA) is the most common joint disease, but no effective and safe disease-modifying treatment is available. Risk factors such as age, sex, genetics, injuries and obesity can concur to the onset of the disease, variably triggering the loss of maturational arrest of chondrocytes further sustained by oxidative stress, inflammation and catabolism. Different types of nutraceuticals have been studied for their anti-oxidative and anti-inflammatory properties. Olive-derived polyphenols draw particular interest due to their ability to dampen the activation of pivotal signaling pathways in OA. Our study aims to investigate the effects of oleuropein (OE) and hydroxytyrosol (HT) in in vitro OA models and elucidate their possible effects on NOTCH1, a novel therapeutic target for OA. Chondrocytes were cultured and exposed to lipopolysaccharide (LPS). Detailed analysis was carried out about the OE/HT mitigating effects on the release of ROS (DCHF-DA), the increased gene expression of catabolic and inflammatory markers (real time RT-PCR), the release of MMP-13 (ELISA and Western blot) and the activation of underlying signaling pathways (Western blot). Our findings show that HT/OE efficiently attenuates LPS-induced effects by firstly reducing the activation of JNK and of the NOTCH1 pathway downstream. In conclusion, our study provides molecular bases supporting the dietary supplementation of olive-derived polyphenols to revert/delay the progression of OA

    Hydroxytyrosol Prevents Increase of Osteoarthritis Markers in Human Chondrocytes Treated with Hydrogen Peroxide or Growth-Related Oncogene \u3b1

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    Hydroxytyrosol (HT), a phenolic compound mainly derived from olives, has been proposed as a nutraceutical useful in prevention or treatment of degenerative diseases. In the present study we have evaluated the ability of HT to counteract the appearance of osteoarthritis (OA) features in human chondrocytes. Pre-treatment of monolayer cultures of chondrocytes with HT was effective in preventing accumulation of reactive oxidant species (ROS), DNA damage and cell death induced by H2O2 exposure, as well as the increase in the mRNA level of pro-inflammatory, matrix-degrading and hypertrophy marker genes, such as iNOS, COX-2, MMP-13, RUNX-2 and VEGF. HT alone slightly enhanced ROS production, but did not enhance cell damage and death or the expression of OA-related genes. Moreover HT was tested in an in vitro model of OA, i.e. three-dimensional micromass cultures of chondrocytes stimulated with growth-related oncogene \u3b1 (GRO\u3b1), a chemokine involved in OA pathogenesis and known to promote hypertrophy and terminal differentiation of chondrocytes. In micromass constructs, HT pre-treatment inhibited the increases in caspase activity and the level of the messengers for iNOS, COX-2, MMP-13, RUNX-2 and VEGF elicited by GRO\u3b1. In addition, HT significantly increased the level of SIRT-1 mRNA in the presence of GRO\u3b1. In conclusion, the present study shows that HT reduces oxidative stress and damage, exerts pro-survival and anti-apoptotic actions and favourably influences the expression of critical OA-related genes in human chondrocytes treated with stressors promoting OA-like features

    Evaluating Ecklonia maxima water-soluble polysaccharides as a growth promoter of tomato seedlings and resistance inducer to Fusarium wilt

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    Alternatives to chemicals for plant management are increasingly used to reduce environmental pollution. Seed treatment with natural products may act as a priming effect by stimulating seedling growth and plant defence responses against fungal pathogens. In this framework, algae produce a wide variety of bioactive metabolites, which can be used in agriculture as biofertilizers or biostimulants. The purpose of this study was to investigate the possible role of water-soluble polysaccharides (WSPs) from the brown alga Ecklonia maxima applied on tomato seed in enhancing plant growth and inducing resistance to Fusarium oxysporum via modulation of multiple physiological parameters and metabolic pathways. Here, we first characterized the E. maxima WSPs by FT-IR spectroscopy, and then we tested the WSPs as growth promoters on tomato seedlings, and the physiological and defence responses of plants during pathogen infection. We found that WSP seed treatment without pathogen challenge stimulated seedling height and root growth by 24.5 and 62.9%, respectively. Under pathogen infection, plants exhibited long-lasting resistance against F. oxysporum until 46 days after seed treatment. The metabolic changes associated with resistance to Fusarium wilt in plant roots were related to an increase in phenols, flavonoids and protein contents as well as a higher chitinase and beta-1,3-D-glucanase enzyme activity. Moreover, PR1a, PR3 and other defence gene expressions were significantly increased. Resistance to F. oxysporum as a result of WSP seed treatment was also supported by FT-IR analysis of tomato roots. Infected roots showed a decrease in the relative intensity of the bands due to the syringyl ring and amide I and amide II in proteins. In contrast, WSP treatment alone and in the presence of the pathogen exhibited a spectral profile similar to that of the control. This research emphasizes the potential role of algal polysaccharides applied by seed treatment in promoting seedling growth and priming plant resistance against soil-borne pathogens

    Jania adhaerens Primes Tomato Seed against Soil-Borne Pathogens

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    Managing soil-borne pathogens is complex due to the restriction of the most effective synthetic fungicides for soil treatment. In this study, we showed that seed priming with Jania adhaerens water-soluble polysaccharides (JA WSPs) was successful in protecting tomato plants from the soil-borne pathogens Rhizoctonia solani, Pythium ultimum, and Fusarium oxysporum under greenhouse conditions. WSPs were extracted from dry thallus by autoclave-assisted method, and the main functional groups were characterized by using FT-IR spectroscopy. WSPs were applied by seed treatment at 0.3, 0.6 and 1.2 mg/mL doses, and each pathogen was inoculated singly in a growing substrate before seeding/transplant. Overall, WSPs increased seedling emergence, reduced disease severity and increased plant development depending on the dose. Transcriptional expression of genes related to phenylpropanoid, chlorogenic acid, SAR and ISR pathways, and chitinase and beta-1,3 glucanase activities were investigated. Among the studied genes, HQT, HCT, and PR1 were significantly upregulated depending on the dose, while all doses increased PAL and PR2 expression as well as beta-1,3 glucanase activity. These results demonstrated that, besides their plant growth promotion activity, JA WSPs may play a protective role in triggering plant defense responses potentially correlated to disease control against soil-borne pathogens
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